Fig 2. TCR nucleotide sequences shared between twins are statistically different from sequences shared between unrelated individuals.
Distribution of log10 Pgen, with Pgen the probability that a sequence is generated by the VJ recombination process, for shared out-of-frame TCR alpha clonotypes between one individual and the other five. While the distribution of shared sequences between unrelated individuals (red curves) is well explained by coincidental convergent recombination as predicted by our stochastic model (blue), sequences shared between two twins (green) have an excess of low probability sequences: 31 sequences with log10 Pgen < −10. For comparison the distribution of Pgen in regular (not necessarily shared) sequences is shown in black.